std::to_wstring

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Defined in header <string>
std::wstring to_wstring( int value );
(1) (since C++11)
std::wstring to_wstring( long value );
(2) (since C++11)
std::wstring to_wstring( long long value );
(3) (since C++11)
std::wstring to_wstring( unsigned value );
(4) (since C++11)
std::wstring to_wstring( unsigned long value );
(5) (since C++11)
std::wstring to_wstring( unsigned long long value );
(6) (since C++11)
std::wstring to_wstring( float value );
(7) (since C++11)
std::wstring to_wstring( double value );
(8) (since C++11)
std::wstring to_wstring( long double value );
(9) (since C++11)

Converts a numeric value to std::wstring.

Let buf be an internal to the conversion functions buffer, sufficiently large to contain the result of conversion.

1) Converts a signed decimal integer to a wide string as if by std::swprintf(buf, sz, L"%d", value).
2) Converts a signed decimal integer to a wide string as if by std::swprintf(buf, sz, L"%ld", value).
3) Converts a signed decimal integer to a wide string as if by std::swprintf(buf, sz, L"%lld", value).
4) Converts an unsigned decimal integer to a wide string as if by std::swprintf(buf, sz, L"%u", value).
5) Converts an unsigned decimal integer to a wide string as if by std::swprintf(buf, sz, L"%lu", value).
6) Converts an unsigned decimal integer to a wide string as if by std::swprintf(buf, sz, L"%llu", value).
7,8) Converts a floating point value to a wide string as if by std::swprintf(buf, sz, L"%f", value).
9) Converts a floating point value to a wide string as if by std::swprintf(buf, sz, L"%Lf", value).
(until C++26)
1-9) Converts a numeric value to a wide string as if by std::format(L"{}", value).
(since C++26)

Parameters

value - a numeric value to convert

Return value

A wide string holding the converted value.

Exceptions

May throw std::bad_alloc from the std::wstring constructor.

Example

#include <iostream>
#include <string>
 
int main()
{
    for (const double f : {23.43, 1e-9, 1e40, 1e-40, 123456789.0})
        std::wcout << "std::wcout: " << f << '\n'
                   << "to_wstring: " << std::to_wstring(f) << "\n\n";
}

Output:

std::wcout: 23.43
to_wstring: 23.430000
 
std::wcout: 1e-09
to_wstring: 0.000000
 
std::wcout: 1e+40
to_wstring: 10000000000000000303786028427003666890752.000000
 
std::wcout: 1e-40
to_wstring: 0.000000
 
std::wcout: 1.23457e+08
to_wstring: 123456789.000000

See also

(C++11)
converts an integral or floating point value to string
(function)